Does anyone know what Cadillac did for the 95-96 FWB's to make the door latches quieter when closing the doors?

Because I was wondering if it's possible to retro fit them for my 94. I am getting annoyed by all that clanking when closing the rear doors, sometimes it feels like the doors are not all the way shut, even though they are.

Also is there a way to somehow make the front doors close a little quieter as well, they always seem to slam shut, and tend to make this vibrating "buzz" sound especially on the passenger side door upon closing. I can tell that GM got cheap here, because the doors don't have that thunk sound when closing, or a secure sound if you know what I mean like most cars today, it's more like they always close hard, and don't have that smooth feel when you close the doors.

Could I use some kind of rubber sleeves on the latches? Has anyone experienced or tried something to quiet the doors on any 93-94 FWB's?